How important is doubling down power to 2 ohm or 1ohm on Hi Fi Speakers on high dynamic range music?

[Speedskater]

What's with the 'RMS Power' is it the 1970's all over again?

 

[MakeMineVinyl]

What's with the 'RMS Power' is it the 1970's all over again?

Sure. Retro is a thing now, right?

 

[RealityCheck18]

1812 Overture?

The sonic boom from the double-loaded cannons at the end resonate down to 8 Hz. How many two-channel type speakers can actually go down to 8Hz accurately and at high volume? Well, that would be a spec to shoot for that is useless in reality. The right way is to use subwoofers, a bunch of them that can move enough air to get the proper SPL.

I used to play Telarc's 1812 Overture with a car audio system--good times! We calibrated the system to know where clipping was, operated it at a click below and let the sealed subs fly! The cops pulled us over for our efforts because most young guys didn't cruise the strip playing classic music.

If you want the 1812 Overture at high SPL levels, skip 2 channel madness and get some really efficient speakers and groups of subwoofers to actually provide the SPL required without clipping the amps or overdriving the subwoofers into power compression, high distortion levels and so on.

Basically, using those speakers it don't matter what amp you use be it a mystical amp or a PowerSoft 20,000 watt stadium amp--you have exceeded the limits of the speakers both in frequency response AND peak SPLs at maximum levels. Not enough rig for the gig!

The Telarc version is a great tune to test speakers/subs and amplifiers. Huge dynamic range coupled with a sonic boom resonating down to 8 Hz is always entertaining. At the minimum, it blows the dust off the woofers and cleans out the ports.

Be aware that I would never use it as a "test" on a 2 speaker system with just an amp operating. The massive dynamics and sonic boom demand subwoofers, limiters on the amplifiers and speakers that can handle very high peak voltages without cooking the voice coils or tearing up the suspension, slamming the voice coil into the magnet or folding the cone if you throw enough power at them. Use the right tool for the job so if you need sub bass, don't use a woofer! Did hear a very convincing playback in a car, quite the sub system which eventually removed the glass from the car and blew it all over the parking lot. Took some serious speaker drivers to provide the peaks though, we used 8" PA mids to take the strain.

If you really want to damage your B&Ws, the opening scene on Edge of Tomorrow is max output at around 10Hz--the Irene Scene on Blackhawk Down chopper blades roll at 7 to 8Hz and for fun... Bass, I Love You has an 8 Hz tone. There is a pipe organ that has a 128 foot long pipe that punches down to 4Hz also... ya know, because 4 Hz is a "double down" of 8Hz! Be a real man, get those woofers woofing some 4Hz because.. you want to play all music--even if the speakers won't do it at all.

 

[MasterApex]

I agree with some of the comments on here. That music was picked especially for the demo.

1. Heavy bass content with no subwoofer meant that it all had to come from those amps.
2. The volume was turned up very high as the room was quite large, probably 30% or so larger than most listening rooms at home.
3. The second track of violins really showed what I am trying to point out. It had very little bass and they were hitting a peak of 28 watts at a very high volume on the preamp.
4. In reality, most people who want accurate bass in large amounts get a quality subwoofer. This will reduce a good portion of the bass and deep bass from the amplifiers. That alone would have dropped those 750 watt peaks by a good bit. It may have shown peaks of only 500 watts which is a big drop. But we will never know as that was not the point of the test.
5. I want to comment again as it can't be overstated. A large room and high volume was used. As I believe he stated it was much higher than anyone would listen to normally. Those violins were screeching like crazy and now your in hearing damage territory. But I can't really tell for sure as an important technical point was left out. What was the listening SPL range? It doesn't have to be specific, just a range. If your in the 60 to 70 range you know that, if in the 100 to 105 range that is something you can also tell with a cheap meter. But to have no idea at all was a let down of the "test". I am making an assumption as 500 watts RMS, 750 watt peaks into most speakers will be the max (or over max) they can play at over the long term, they are beating the drivers pretty hard. I have tested drivers to failure many, many times. That was almost a torture test and as torture tests go a very short one that didn't cause any problems. After a few hours they may (we will never know) have let the smoke out of the speaker box!

To get me to respond like this shows that this is a fantastic thread! Very enjoyable.

Do you have opinion what amplifier spec/measurement that may explain why the certain amplifier have more dynamic than others? Is the doubling down a measure of its dynamic capability?
Thanks

 

[ahofer]

Everything is about "the doubling down", and all comments should be interpreted with respect to their relevance to "the doubling down".

OMG! --- have you been running into GeorgeHiFi over at Audiogon?

That's the one. I was thinking it was millercarbon of the thousand amps.

 

[pjug]

Reading about the equipment folks would want to hear a recording of a cannon, I have to wonder if you might just want to buy a cannon.

 

[audio2design]

Everything is about "the doubling down", and all comments should be interpreted with respect to their relevance to "the doubling down".

That's the one. I was thinking it was millercarbon of the thousand amps.

No that would be not so curious George. While his is very anti-fuser and most things, the has some weird ideas about amplifiers and how they work. Basically he does not know how they do, and fill in the gaps with guesses based on limited knowledge. Millercarbon is just generally wrong about almost everything, but that has never stopped him or his tall tales.

 

[ahofer]

No that would be not so curious George. While his is very anti-fuser and most things, the has some weird ideas about amplifiers and how they work. Basically he does not know how they do, and fill in the gaps with guesses based on limited knowledge. Millercarbon is just generally wrong about almost everything, but that has never stopped him or his tall tales.

I’ve noticed Millercarbon is all-in for Ted Denney, which is consistent.

 

[audio2design]

I’ve noticed Millercarbon is all-in for Ted Denney, which is consistent.

We do not mention he who must not be named. That place is just bizarre. Such characters on there, many quite convinced of their brilliance with not remotely a clue what they are talking about. I love the philosophical techno babble ramblings of Teo_Audio, not to be confused with the philosophical bumbling ramblings of Mahgister. The moderators really pretty the "core". Millercarbon is abusive and insulting without fail, but short of overt racism, never gets a comment removed, while anyone who rocks the "old timers" gets banned.

 

[Spkrdctr]

So if my speaker is a complex load (not efficient , low impedance, high phase angle, etc) and I want to be able to get the full dynamic of any music out of my speaker, what is the spec I should look for in choosing Amplifier?
Double down = more headroom ?

Yes. All the rest doesn't matter as it is not user adjustable.

 

[Spkrdctr]

Do you have opinion what amplifier spec/measurement that may explain why the certain amplifier have more dynamic than others? Is the doubling down a measure of its dynamic capability?
Thanks

For an easy answer, yes. If your amp/receiver will handle 4 ohms easily, then it will have no problem handling any music UNLESS you run a test at silly high volumes. Buy turning amps up to 11 you can always push them until they meet their limits. Normal usage, they have plenty of power. A normal 200 8ohm/400 4ohm amp will usually get the job done or a 300/600 to 500/1000 for the power needy.

 

[MasterApex]

I plan to replace the old Krell KSA200s with something newer (so was testing Class D Amp).

Therefore, I am asking the question whether the double down attribute is important (in playing dynamic music) for my next amplifier purchase/upgrade. Sounds like the consensus is "it is".

 

[MakeMineVinyl]

I plan to replace the old Krell KSA200s with something newer (so was testing Class D Amp).

Therefore, I am asking the question whether the double down attribute is important (in playing dynamic music) for my next amplifier purchase/upgrade. Sounds like the consensus is "it is".

No, strictly it is not. The "doubling" of power into 1/2 the impedance is in reality a marketing moving-target. In some instances a manufacturer may believe it is in their best marketing interests to choose an 8 Ohm rating which is a bit more conservative so that they can market the 'ability' of twice the power into 4 Ohms. We make an amplifier which can in reality do this without hocus-pocus, but it takes a lot of design work and a lot of money. Obviously closer to the ideal is better than a large discrepancy between the impedances, but be aware that there is a lot of marketing involved not just in amplifier power but in audio in general. There are hard electronic facts which are not bendable, but marketing tries to bend them at every opportunity.

 

[Spkrdctr]

but be aware that there is a lot of marketing involved not just in amplifier power but in audio in general. There are hard electronic facts which are not bendable, but marketing tries to bend them at every opportunity.

No, say it isn't so!! Audio gear sold on incorrect measurements? Also, known as lying. Marketing bending scientific principles? Would that be snake oil? Here I thought audio was an honest business.....well compared to a heroin dealer. Audio sales=crack/heroin dealer. If everyone bought audio gear with that in mind, much of the audiophoolery would go away. Remember if your talking to a salesman there is an 80 to 90% chance they are lying. Thoughts to live by!

 

[DonH56]

Heroin is cheaper.

 

[MakeMineVinyl]

No, say it isn't so!! Audio gear sold on incorrect measurements? Also, known as lying. Marketing bending scientific principles? Would that be snake oil? Here I thought audio was an honest business.....well compared to a heroin dealer. Audio sales=crack/heroin dealer. If everyone bought audio gear with that in mind, much of the audiophoolery would go away. Remember if your talking to a salesman there is an 80 to 90% chance they are lying. Thoughts to live by!

A salesman at a professional audio company I used to work for told me outright that 'salesmanship is controlled lying'.

 

[DonH56]

A salesman at a professional audio company I used to work for told me outright that 'salesmanship is controlled lying'.

Too often it is not all that controlled...

 

[MasterApex]

Ahofer posted this video

and very useful the materials that explain apparent power, real power, and reactive power.
https://www.pema.ie/TECHTALK LIBRARY/APT/True vs. Apparent Power.pdf
http://www.cromptonusa.com/Watt_Var_VA.pdf
https://www.audioholics.com/loudspeaker-design/understanding-impedance-electrical-phase/page-2

I am looking for technical attribute (may be it not yet defined or published in measurement) that explains the higher sound quality dynamic.
I was asking whether double down is the attribute because that is what is published in spec but there may be a new attribute that is not yet found or published that explains the better dynamic range.

 

[DonH56]

Dynamic range is a function of noise floor (SNR) and power output. Different manufacturers may specify amplifiers differently, even within their own product line. A conservatively specified amplifier may actually provide more power than one rated for higher power especially if it is specified for low-impedance loads and "doubling down". Thermal (heat) requirements, power supply capacity, output device safe operating area, and a myriad of other factors come into play. The opposite is also true; an amplifier not rated to "double down" all the way to 2 ohms may provide more power but simply not have the heat sink and power supply to sustain long-term high-current output for low loads. So it might not be rated to "double down" but in real life may sound far more powerful.

Like many things, there is not a simple single specification that tells everything about the amp.

 

[MakeMineVinyl]

Dynamic range is a function of noise floor (SNR) and power output. Different manufacturers may specify amplifiers differently, even within their own product line. A conservatively specified amplifier may actually provide more power than one rated for higher power especially if it is specified for low-impedance loads and "doubling down". Thermal (heat) requirements, power supply capacity, output device safe operating area, and a myriad of other factors come into play. The opposite is also true; an amplifier not rated to "double down" all the way to 2 ohms may provide more power but simply not have the heat sink and power supply to sustain long-term high-current output for low loads. So it might not be rated to "double down" but in real life may sound far more powerful.

Like many things, there is not a simple single specification that tells everything about the amp.

The thermal dissipation aspect is becoming a very big deal in designing new amplifiers, especially multi-channel ones. Actually, because of various requirements and regulations, its becoming an incredibly big deal.